ILX Lightwave LDT-5900 Series User Manual page 137

3
01_10
C A L I B R A T I O N A N D T R O U B L E S H O O T I N G
2l Calculate the VTE Measurement Slope and Offset using the following formulae:
m
VTE
b VTE
VTE
2m Enable Cal Mode by entering the remote command MODE CAL.
2n Enter the new calibration values using the command: CAL:VTE m
2o Save the new values to flash memory by using the CAL:SAVE command.
2p Return to ITE Mode by the MODE ITE command.
2q To verify the cal values have been correctly stored, use the CAL:VTE? command to
query them.
ITE MEASUREMENT CALIBRATION
3a Set output to -5 A (-4.5 A if 5948 to prevent current limit from enabling) and connect
the DMM (Digital MultiMeter) across the TE Cal resistor to measure voltage. Pay
attention to polarity.
3b Allow one minute for current to stabilize if output has just been enabled.
3c Record the TE current (ITE
MEASure:IADC? command.
Note: Note: Allow a minimum of 2 seconds to elapse between readings to ensure the
instrument has had enough time to perform another round of measurements.
3d Record the TE voltage (VTE
3e Set output to +5 A (+4.5 A if 5948).
3f Record ITE (preferably via MEASure:IADC?).
UUT2
3g Record VTE .
DMM2
3h Disable output.
3i Calculate the ITE Measurement Slope and Offset using the following formulae:
m
ITE
VTE
b
ITE
3j Enable Cal Mode by entering the remote command MODE CAL.
3k Enter the new calibration values using the command: CAL:ITE m
VTE VTE
DMM 2 DMM
VTE VTE
UUT 2 UUT 1
m VTE
DMM 2 VTE UUT
) as measured by the UUT using the
UUT1
) as measured by the DMM.
DMM1
VTE VTE
DMM 2 DMM
R ITE ITE
TE UUT 2 UUT
DMM 2
m ITE
VTE UUT
R
TE
Ca libra t ion Procedure
1
2
, b
VTE
1
1
2
, b
ITE ITE
5
C H A P T E R
VTE
121
LDT-5980/ 5948